Magnetron of the cavity resonator type



Nov. 10, 1953 K. H. J. BOKHOVE 2,659,031

MAGNETRON OF THE CAVITY RESONATOR TYPE Filed March '7, 1952 2Sheets-Sheet 1 INYENTOR Karel Herman Jon Bokhove Agent 1953 K. H. J.BOKHOVE MAGNETRON OF THE CAVITY RESONATOR TYPE 2 Sheets-Sheet 2 FiledMarch 7, 1952 Patented Nov. 10, 1953 Karel Herman Jan Bokhove,Eindhoven, Netherlands, assignor to Hartford National Bank and TrustCompany, Hartford, Conn., as trustee Application March 7, 1952, SerialNo. 275,403

Claims priority, application Netherlands April 14, 1951 30laims.((1315-40) 2 This invention relates to magnetrons of the cavityresonator type.

Heretofore, magnetrons of the foregoing type generally comprised ananode block, containing resonant cavities, sandwiched between terminalmembers having a single flat surface. The terminal members were securedto the anode block by means of setting studs and solder interposedbetween the mating surfaces thereof. This arrangement resulted indifilculties in that the solder would flow toward the resonant cavitiesresulting in losses and changes in the frequency for which the magnetronwas designed.

It is an object of the invention to obviate the aforesaid difficulties.

This and other objects of the invention will appear from the descriptionthat follows.

According to the invention, a magnetron of the foregoing type comprisesan anode block having end faces and defining at least one resonantcavity opening into a discharge space. The anode block is provided witha passageway having a central portion of given width and end portionshaving a greater width co-operating therewith to form an H-shapedchannel for connecting the cavity to some form of hollow wave guide. Asubstantially annular rim portion of the anode block which is eccentricwith respect to the cavity and the discharge space is raised ordepressed with respect to the surface of the block so that the innerperipheral border thereof is spaced by a given distance from theresonant cavity and the H-shaped channel. A pair of terminal membershaving complementary surfaces adapted to interfit with the end faces ofthe block are affixed thereto by solder interposed between the annularrim portion of the block and the corresponding surface of the terminalmember, the surface portion adjacent the annular rim portion serving toprevent the entry of the solder into the resonant cavity or the H-shapedchannel. The mating surfaces of the annular rim portion of the block andthe corresponding surface of the terminal members are spaced by a smalldistance, of the order of about a few hundredths of a millimeter, foraccommodating the solder. The peripheral edge of the small enclosurecontaining the solder may be tapered or otherwise widened to form agroove for holding a wire or strip of solder.

The invention will now be described with reference to the accompanyingdrawings wherein:

Fig. 1 is a view, in cross-section, of one form of magnetronexemplifying the invention;

Fig. 2 is a plan view of an anode block;

Fig. 3 is a perspective view of the block shown in Fig. 2;

Fig. 4 is a perspective view of. a terminal mem- Fig. 5 is a view, incross section, of another form of magnetron exemplifying the invention.

Referring to the figures, an anode block I is sandwiched between upperand lower terminal members 3 and 2, respectively. 'A plurality ofresonant cavities II to I8 open into a common discharge space Ill.Opposite ends of the resonant cavities II to I8 terminate in upper andlower terminal spaces which are designated 8 and 9, respectively. Theblock I is provided with a passageway I9 and channels 20' and ,2Iforming an H-shaped channel extending from one of the cavities II andutilized for transmitting the energy produced in the magnetron to, forexample, a hollow wave guide not shown which may be secured toprojecting lugs 26, 21, 2B of the lower terminal member 2, the block Iand the upper terminal member 3, respectively. The edge portions of theupper surface 4 and the lower surface 6 are depressed as shown at 5, 1respectively, to form annular rim portions which are eccentric withrespect to the discharge space I 0 and in which the inner peripheralborder region of the depressed portions 5, l are spaced by a givendistance from the resonant cavities II to I8 and the channels 20, 2 I.

The terminal members 2, 3 are provided with recesses 23 which conform tothe surfaces 4, 6 of the block and openings 24, 25 for accommodatingpole shoes and a cathode not shown. The terminal members 2, 3 and theblock I are shaped such that a space of a few hundredths of a millimeterseparates the depressed surface portions 5, 6 from the correspondingsurface portions 22 of the terminal members 2, 3. The solder forsecuring the terminal plates 2, 3 to the block I is confined within theabove space and prevented from entering the channels 20, 2I and thecavities II to I8 by the peripheral barrier separating the depressedportions 5, 6 from the surfaces 4,

the block I as shown in Fig. 5 in lieu of depressreadily apparent tothose skilled in the art with- I out departing from the invention asdefined in the appended claims:

What I claim is:

1. A magnetron anode structure of the cavity resonator type comprisingan anode block having end faces and defining a resonant cavity openinginto a discharge space, said block being provided with a passagewayhaving a central portion of given width and end portions having a widthgreater than said given width thereby forming an H-shaped channel forconnecting the resonant cavity with a hollow wave guide, each of saidend faces having one portion depressed with respect to another portionthereby defining a substantially annular rim portion eccentric I withrespect to said resonant cavity and said discharge space and having aninner peripheral border spaced by a given distance from the resonantcavity and the H-shaped channel, terminal plates having complementarysurfaces interfit ting with the end faces of said block, and soldermeans securing the terminal i'nembers to said block.

2. A magnetron anode structure of thecavity resonator type comprising ananode block having end faces and defining a resonant cavity opening intoa discharge space, said block being provided with a passageway having acentral portion of given width and end portions having a width greaterthan said given width thereby forming an H-shaped channel for connectingthe resonant cavity with a hollow wave guide, each or said end faceshaving one portion depressed with respect to another portion therebydefining a substantially annular rim portion eccentric with respect tosaid resonant cavity and said discharge space and having an innerperipheral border spaced by a given distance from the resonant cavityand the H-shaped channel, terminal plates having complementary surfacesinterfitting with the end faces of said block, said annular rim portionbeing spaced by a small distance from the coresponding surface portionof said terminal members thereby defining a small space, and soldermeans located in said space and securing the terminal members to saidblock.

3. A magnetron anode structure of the cavity resonator type comprisingan anode block having end faces and defining a resonant cavity openinginto a discharge space, said block being provided with a passagewayhaving a central portion of given width and end portions having a Widthgreater than said given width thereby forming an Hshaped channel forconnecting the resonant cavity with a hollow wave guide, each of saidend faces having one portion depressed with respect to another portionthereby defining a substantially annular rim portion eccentric withrespect to said resonant cavity and said discharge space and having aninner peripheral border spaced by a given distance from the resonantcavity and the H- -shaped channel, terminal plates having complementarysurfaces interfitting with the end faces of said block, said annular rimportion being spaced byv a few hundredths of a millimeter from thecorresponding surface portion of said terminal members thereby defininga small space, and solder means located in said space and securing theterminal members to said block.

KAREL HERMAN JAN BOKHOVE.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,466,922 Wax Apr. 12, 1949

